Regardless of the privacy implications, or lack thereof, it should change search irreversibly and it should make it better, in all cases.

Well, it would change search irreversibly if it weren't for the small detail that, for Google, social equals Google+ and nothing else.

Private stuff you and your friends have posted to Google+ will show up in search results, stuff from Facebook or Twitter will not, apart from the things that are public and have been available up until now as well.

There are good reasons for this, neither Facebook nor Twitter is allowing Google to access content that is not shared publicly with the world. That makes sense from a privacy point of view, but users don't have the option of allowing Google access if they want to.

Plenty of other third-party apps do get access to your personal data. Start playing any Facebook game and you'll be asked to relinquish control over your friends list, your wall and so on.

But Google can't do the same for something that you may actually want, i.e. a better way of finding content from your friends, as opposed to apps that use your data just to spam your friends.

Don't cry too much for poor old Google though, while it may very well like to add more data from other social networks to search results, it is content with promoting Google+ any chance it gets as well.

It passed up the chance of striking a deal with Twitter for access to the full, real-time tweet stream, opting to rely on Google+ instead.

Its social network has some tens of millions of registered users already. If it continues to grow at its current pace, it will reach 100 million users in a couple of months at the most.

It may never become Facebook, but if Google can use its search engine to lure people into Google+ while, at the same time continue pointing the finger at the likes of Facebook for not 'opening up' data, it will gladly do so.